Propylene (propene) is a commercially important olefin product and a byproduct of oil refining and natural gas processing. Propylene is also produced by on-purpose production methods, such as butene isomerization combined with olefin metathesis chemistry (see, for example, FIG. 1). Olefin metatheses, which are also known as disproportionation, are reversible reactions in which double bonds of, for example, ethylene and 2-butene (B2) are broken and then reformed as propylene. WO3 supported on SiO2 is one type of disproportionation catalyst that has been used, and MgO is one type of isomerization catalyst that has been used. The chemistry involves many side reactions in the disproportionation (DP) reactors (FIG. 2), including, e.g., the half productive route for propylene via butene (B) self-metathesis and undesirable consumption of product propylene with 1-butene (B1) to produce higher olefins (C5+ olefins) and ethylene. Current methods are energy intensive, relying on high heat (e.g., 650° F.), and significant quantities of isomerization catalyst, i.e. a high weight ratio of isomerization catalyst to the disproportionation catalyst (see, e.g., FIG. 3).